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FOR E FUTURIA G R R S! U E N E R P
Volume 67 I August 2, 2021 I email: agined@globalHQ.co.nz I w w w.farmersweekly.co.nz WeatherWatch with Phil
Improving our drainage systems
FOUR SEASONS IN ONE DAY
There's a reason it was a NZ band (Crowded House) that sang the song Four Seasons In On Day - it sums up our weather so well! In particular, the western side of NZ has changeable weather (due to westerlies being the prevailing wind). Changeable weather is the way of life in NZ and our mountains and ranges - plus our location on earth (being partially in the Roaring Forties belt of wind around the Southern Ocean) - means we have a lot of variety. The wind direction shifting around can make for some regions to be stunning, sunny and mild, while on the other side of the ranges it may be cloudy, wet and cold.
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YOUR CHALLENGE is to find which parts of NZ have the most extreme differences weatherwise - all on the same day!
Have a go: 1 Go to https://farmersweekly.co.nz/section/ agribusiness/view/drain-impact-under-spotlightin-hawkes-bay
The first article suggests five main ways to reduce contaminants entering tile drains, what are these? Are there any that you consider more important than others? Or are they all of equal importance? Tile drains are used in cropping, horticulture and grazed pastures. The second article looks at how wetlands can help to treat tile drainage flow from intensively grazed pastures. How do these wetlands help to reduce nutrient losses from pastures before they reach receiving water bodies?
2 Read the article “Drain impact under spotlight in Hawke’s Bay”. 3 What are tile drains and how do they work? 4 What factors contributed to Hawke’s Bay being chosen to study the impact of tile drains upon freshwater quality?
e What environmental factors affect the
STRETCH YOURSELF:
STEPS: 1 Head here https://www.weatherwatch. co.nz/maps-radars/rain/rain-forecast and find a day over the coming week that has variety (ie, windy in some regions, calm in others, wet weather for some etc)
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2 Then visit www.RuralWeather.co.nz and search various locations around NZ to find the weather forecasts 3 Find places that are: Sunny, raining (or cloudy), mild, cold, windy and calm... and anything else (like foggy, frosty or thunderstorms). Try to find 6 very different forecasts all on the same day.
Example of NZ’s weather variety at one moment in time:
performance of wetlands?
There are a number of articles that outline ways to mitigate contaminants from entering waterways including one from Environment Southland: https://www. es.govt.nz/repository/libraries/id:26gi9ayo517q9stt81sd/ hierarchy/community/farming/good-managementpractice/documents/Land%20sustainability%20 guides%20and%20factsheets/A%20guide%20to%20 reducing%20contaminants%20entering%20tile%20 drains.pdf, and things like constructions of wetlands for treatment of tile drainage: https://niwa.co.nz/ sites/niwa.co.nz/files/import/attachments/NZCWguide4press _ small.pdf
e List the five stages of wetland construction with a brief outline of each stage.
e What are the roles of plants in a wetland?
Can you name three plants that are well suited to wetlands? Along with where they are best used when planting (i.e. flooded zone, embankments etc) A guide to reducing contaminants entering tile drains.pdf
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New Zealand Guidelines for Constructed Wetland Treatment of Tile Drainage
This graph shows stock numbers over the last 30+ years.
Got your own question about how the weather works? Ask Phil! Email phil@ruralweather.co.nz with your question and he could answer it on the Weather Together podcast!
DID YOU KNOW?
STRETCH YOURSELF: 1 What are some factors that have driven the decline in total sheep numbers?
Have a go: 1 Have a look at each species listed on the graph, which has had the most significant change? 2 Around 2007, dairy cattle numbers grew while beef cattle numbers tightened. Why do you think this is? 3 What year did sheep numbers peak?
2 In 1990 the total sheep numbers were around 60 million, compared to around 22 million in 2020. What is the percentage difference between these two figures? 3 What do you think total stock numbers will look like in another 10 years? 4 Give some examples of the pressures on NZ farmers at the moment.
An Irish postdoctoral researcher has shown a disparity between the measured methane emissions of cows grazing at pasture compared to the current estimate used by the national inventory. Have a read at: https://www.farmersjournal. ie/moorepark-trials-indicate-dairy-cowmethane-production-overestimated-634677 What is your take on this? Why do you think that there is currently such a disparity between Ben’s research and the national inventory estimate? Do you think that there is a need for more of this type of research? Why or why not?
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